Don't lint html.erb and html.ruby scopes (#154)

* Don't lint html.erb and html.ruby scopes

This linter doesn't handle ERB and Ruby, but it pretends to which
causes a lot of false errors on ERB templates to the point where it's
nearly impossible to edit any ERB file with htmlhint enabled.

Additionally there is a proper ERB linter available in the linter-erb
package.

Author: ricardograca

package.json

@@ -18,11 +18,9 @@
       "default": [
         "text.html.angular",
         "text.html.basic",
-        "text.html.erb",
         "text.html.gohtml",
         "text.html.jsp",
-        "text.html.mustache",
-        "text.html.ruby"
+        "text.html.mustache"
       ],
       "items": {
         "type": "string"